isoTimestamp only accepts UTC timestamps

[macarie]

It looks like ISO_TIMESTAMP_REGEX validates only UTC timestamps (ending with Z). But the standard also defines the possibility of having offsets.

From my understanding, the following formats should all be considered as valid ISO timestamps:

• <time>Z
• <time>±hh:mm
• <time>±hhmm
• <time>±hh

If you consider it a bug, I'd happily open a PR 🙂

[fabian-hiller]

Thank you for creating this issue! Do you have a use case for this functionality? Can you share some example code?

[macarie]

@fabian-hiller, while working with a Rails backend, we get timestamps with offsets like this: 2023-08-09T18:04:15.582+02:00.

The idea was to validate the field using string([isoTimestamp()]), but the validation fails as it doesn't have the expected format (→ ending with Z).

The offset is valuable in some use cases, as it can be used to determine the event's local time without pulling data from other sources (geolocation, etc.). For example, when selling tickets for a concert in the US, just the offset would be enough to show both the event's local time and the user's local time. But this example can be extended to flights, conferences, etc.

Considering that it seems to be part of the accepted standard, I think this should be handled by the default regex.

[fabian-hiller]

Thank you for the info! Feel free to create a PR and expand the current regex.

[fabian-hiller]

Should be fixed 🙌